In recent years, a white LED package that is one type of a semiconductor light-emitting apparatus is widely used as an alternative to a conventional lighting fixture, such as a fluorescent lamp. It is generally known that a white LED can be achieved by combining a blue LED which is one type of the semiconductor light-emitting device and a yellow phosphor which is a wavelength conversion material. The white LED generates white light as follows. The blue LED emits blue light (primary light) and the blue light excites a yellow phosphor to generate yellow light (secondary light). The blue light that does not excite the yellow phosphor is mixed with the yellow light so as to produce white light.
For example, Patent Citation 1 discloses an LED package having a blue LED chip and a phosphor plate made of a synthetic resin in which yellow phosphor particles are dispersed.
In addition, Patent Citations 2 and 3 each disclose a phosphor plate made of sintered light-emitting ceramics.    Patent Citation 1: Japanese Unexamined Patent Application Publication No. 2003-347061    Patent Citation 2: Japanese Unexamined Patent Application Publication No. 2006-49410    Patent Citation 3: Japanese Unexamined Patent Application Publication No. 2007-150331